Just noticeable difference of source-receiver distances in the auralization process using speech and music signals

Abstract

The precision of source-receiver transfer functions is of importance to provide reliable and ecologically valid results in auralization. Recently the overall just noticeable difference (jnd) in signals obtained from the convolution of music with slightly varying source-receiver transfer functions was determined using a paired comparison procedure (sound are equal/are different) and estimating the jnd from the 75% point on the psychometric curve. JNDs were 3.55 cm for dislocations approaching the source and 3.46 cm if going away from the source. Now we present the results from tests using a speech signal convolved with the same simulated impulsive responses of different source-receiver positions making 3 sets of 23 stimuli pairs. Each one represents receiver dislocations in one dimension: x, y, and z. The jnd using a speech signal was found to be 3.86 cm when approaching the source and 3.97 cm for the opposite direction. The difference calculated between the jnd of the two tests was 0.314 cm (approaching the source) and 0.506 cm (in the opposite direction). Further tests will be done using noise signals and an overall jnd will be computed.